Pyridoxal-5'-phosphate as an oxygenase cofactor: Discovery of a carboxamide-forming, α-amino acid monooxygenase-decarboxylase.

ABSTRACT: Capuramycins are antimycobacterial antibiotics that consist of a modified nucleoside named uridine-5'-carboxamide (CarU). Previous biochemical studies have revealed that CarU is derived from UMP, which is first converted to uridine-5'-aldehyde in a reaction catalyzed by the dioxygenase CapA and subsequently to 5'-C-glycyluridine (GlyU), an unusual β-hydroxy-α-amino acid, in a reaction catalyzed by the pyridoxal-5'-phosphate (PLP)-dependent transaldolase CapH. The remaining steps that are necessary to furnish CarU include decarboxylation, O atom insertion, and oxidation. We demonstrate that Cap15, which has sequence similarity to proteins annotated as bacterial, PLP-dependent l-seryl-tRNA(Sec) selenium transferases, is the sole catalyst responsible for complete conversion of GlyU to CarU. U

SUBMITTER: Huang Y 

PROVIDER: S-EPMC5798378 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature